L2 review charge

	The Level 2 trigger system for CDF has made excellent progress
since the last review on December 7, 2001.  The new magicbus and TTL
arbitration have eliminated the need for the firmware
enforced arbitration delays, and will probably serve CDF's needs
for the remainder of run 2a with only minor additional hardware
modifications.  In reading the committee report from that review,
it is interesting to see that many of the things discussed there,
such as TTL arbitration, and optical splitters for distribution to
upper and lower crates, are now implemented.  
	It is clear that the trigger preparations for Run 2b will 
depend on the performance of the present system.  We request
that the committee examine the present L2 system and evaluate it against
what CDF will need for Run 2b.  This means evaluating the system performance
in its present state and understanding what is left to be done to bring
the system to its Run 2a baseline level.  The evaluation of
the performance should include L1 rate capacity, deadtime, reliability, 
and spares status.  The L2 muon board is an important component of 
the baseline system which is not yet installed in B0.  The 
committee should evaluate the status and the schedule for delivery 
and commissioning of this board.  The committee should determine 
the schedule for bringing the present system to its "final" 
configuration.  At that point, the committee should determine what, 
if any, changes will need to be made to the current L2 trigger 
system to meet the physics bandwidth requirements for run 2b, as 
specified in the run 2b TDR.

One can imagine that some of the options are:

	 1) Retain the current system, if performance is satisfactory.
	 2) Upgrade the Alpha boards to the D0 L2 Beta.
	 3) Switch to a new L2 decision crate system by replacing the
		interface boards, magic bus and alphas with a common 
		interface board design and new processors.
  

Understanding the implications for cost, schedule, and manpower of 
all of the options above is needed to understand the feasibility of 
each, so should be included in the report.